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ohland
07-10-2014, 07:41 PM
For diversion today, I was idly stabbing myself with a fork. After enough misery resulted, I found a post on Cast Boolits that suggested using a like case, choose a similar boolit size, and use the minimum load as maximum. The 6.8mm Rem SPC is @ 34.8 gr of water, the 25-35 is pretty close at 37 grains of water (in comparison, the 7-30 Waters is supposedly 45 grains of water). Not sure if that is what will happen, but I whipped out my Cornell's reprinting of the Lyman Handbook of Cast Boolits, circa 1958, unsteadily weaved my way to page 171, and found the 110 grain, gas check load for the 25-35 (the 280468 S is @ 109 loobed, sized, and GCd) .

Unique / 8.3 gr / 1630 fps
Unique / 5.0 gr / 1170 fps

Methinks I will dump 5.0 gr of You-Neek into a number of primed 6.8mm Rem SPC cases, top em all off with 280468 S boolits (sized to .278). No ideal (pun not intended) of the COL yet, need to find the 6.8mm Rem SPC dies and check on neck sizing first. Have to pull my only short M die body and toss the 27R stem into it.

http://leeprecision.com/cgi-data/instruct/VMD.pdf
VMD Factor * charge in grains = volume cc
.10920 (UNIQUE) * 5.0 = 0.546 cc which is what in grains of water...

autofix4u
07-13-2014, 04:02 PM
Sounds like a good plan. 5.0 gens should be a great place to start. I suspect you will find the load you are looking for between 7.5-8.5 grns. Good luck in your endeavor.

ohland
07-14-2014, 09:21 PM
I ordered a set of Lee 6.8mm Remington SPC dies and an auto prime shell holder (for my hand primer) from Natchez. They haven't sent me any real tracking number yet (for UPS/FedEx/USPS...), expect sometime later this week.

I _could_ use a set of RCBS dies, but the seater is a single-diameter and my concern is that it would be a bee-ach to clean out loob in the top of the seater from boolits.

:cbpour:

runfiverun
07-15-2014, 02:33 AM
keep the lube in the lube groove and make it stiff enough to not migrate.
then you don't gotta worry about it getting up there.

ohland
07-16-2014, 09:49 AM
keep the lube in the lube groove and make it stiff enough to not migrate.
then you don't gotta worry about it getting up there.

Sure thing. When I become a master caster, my loobs will be produced to that level of perfection... :) Really, now. I am amazed that it works tolerably well, in spite of graduating from college....

Lee dies work well enough for my loob monkey skills, and even if my loobs are wanton, er, wanting, my limited skills can easily handle unscrewing the stem and cleaning out the inner surfaces.

Always plan for failure and consider failure modes. Not that I plan to fail, but eventually, the cold uncaring foo bird of fate will drop one on you when it is unexpected least.

ohland
07-16-2014, 09:51 AM
I sure hope FedEx knows that there is a bit of distance between Madison and where I live...

Status: On FedEx vehicle for delivery -

Service: FedEx Ground



07/16/2014 06:54
On FedEx vehicle for delivery

MADISON WI

ohland
07-16-2014, 06:43 PM
Swabbed out the seater die, replaced the Lee no-lock die with a Hornady Sure-Loc, set up the UPM, scale, and press. Loob monkey did the chunka-chunka.

110861

Some thoughts on the 280468S in a T/C Contender 6.8mm Remington SPC 23" rifle barrel.

Whether you want it or not, the round will be about 2.165 COL when you close the action. That equates to about .050 engagement of the gas check in the neck.

Thoughts of the 280468S w/GC .802 long. Using my Hornady LnL ogive gauge, the distance from case head to ogive is 1.950. Measuring just the boolit w/GC, it is .595 from bottom of GC to ogive.

What is the proper way to put this? I want to push the leade out at least .1 to .2 inch. The chamber and neck are OK as the case fits nicely. Just that the boolit won't seat far enough out.

[smilie=b:

ohland
07-23-2014, 02:30 PM
Picked up a set of Millett Angle-Loc rings. Now to "get it on"...

ohland
07-28-2014, 03:45 PM
Well, the load looks to be very promising, but the Leopold 3-9 scope ran out of vertical adjustment. 5 boolits at 25 yards.

111953

Here is 10 boolits, holding half-buttockedly on the outer ring to get the impact into the black
111954

Looks very promising, will have to get a scope with better adjustment.